fix(symfony): revert json schema bc break (#6903)

fixes #6753

Author: soyuka

src/Symfony/Bundle/Resources/config/json_schema.xml

@@ -16,7 +16,7 @@
         <service id="ApiPlatform\JsonSchema\TypeFactoryInterface" alias="api_platform.json_schema.type_factory" />
 
         <service id="api_platform.json_schema.schema_factory" class="ApiPlatform\JsonSchema\SchemaFactory">
-            <argument>null</argument>
+            <argument type="service" id="api_platform.json_schema.type_factory" on-invalid="ignore"></argument>
             <argument type="service" id="api_platform.metadata.resource.metadata_collection_factory" />
             <argument type="service" id="api_platform.metadata.property.name_collection_factory" />
             <argument type="service" id="api_platform.metadata.property.metadata_factory" />